Effect of seasonal burning on biomass, net primary productivity and recovery in Iseilema grassland community of Bundelkhand region (U.P.), India

Abstract

Present study was undertaken to assess the recovery in terms of biomass following seasonal burning of protected Iseilema laxum grassland at Orai (Jalaun), India over a period of one year. The experimental site was divided into three equal plots. Plot I was burnt twice (January and May), plot II was burnt once (January) and plot III was kept unburnt and was used for comparison. Burning stimulated the growth of shoot and root components of the plant but disfavoured the growth of rhizomes. However, average total plant biomass of burnt plots (1284 gm-2 and 1446 gm-2 in plot I and II respectively) could not return to the level of control plot (2196 gm-2 in plot III). Productivity of rhizome declined with the frequency of burning whereas it increased for shoot and root. The concomitant decline in the productivity of rhizome, the most critical component of perennial grassland commands caution. Long-term studies are necessary to establish the critical limit to which rhizome productivity and biomass can decrease yet the grassland can still be maintained for sustained increased level of production. Summer burning prior to rains showed promising result for higher production and thereby the greater recovery rate of biomass as compared to winter burning.